Zuul

• 网关，智能路由、访问过滤
• 默认会用ribbon负载均衡
• application.yml

  • zuul:
            prefix: /v1
            routes:
                hiapi:
                    path: /hiapi/**
                    serviceId: erp-consumer-metadb
                    # url: http://localhost:8762  # 这样写不会做负载均衡
                    # serviceId: hiapi-v1
     
    ## 手动url负载均衡
        # ribbon: 
        #   eureka:
        #     enabled: false
        # hiapi-v1:
        #   ribbon:
        #     listOfServers: http://localhost:8762,http://localhost:8763

• 案例
  • 过滤

    • import static org.springframework.cloud.netflix.zuul.filters.support.FilterConstants.PRE_TYPE;
              @Component
              public class MyFilter extends ZuulFilter {
       
                  private static Logger log = LoggerFactory.getLogger(MyFilter.class);
       
                  @Override
                  public String filterType() {
                      return PRE_TYPE;
                  }
       
                  @Override
                  public int filterOrder() {
                      return 0;
                  }
       
                  @Override
                  public boolean shouldFilter() {
                      return true;
                  }
       
                  @Override
                  public Object run() {
                      RequestContext ctx = RequestContext.getCurrentContext();
                      HttpServletRequest request = ctx.getRequest();
                      log.info(String.format("%s >>> %s", request.getMethod(), request.getRequestURL().toString()));
                      Object accessToken = request.getParameter("token");
                      if (accessToken == null) {
                          log.warn("token is empty");
              //
              //            ctx.setSendZuulResponse(false);
              //            ctx.setResponseStatusCode(401);
              //            try {
              //                ctx.getResponse().getWriter().write("token is empty");
              //            }catch (Exception e){
              //
              //            }
                          return null;
                      }
                      log.info("ok");
                      return null;
                  }
              }

  • 熔断

    • @Component
              public class MyFallbackProvider implements ZuulFallbackProvider {
                  @Override
                  public String getRoute() {
                      return "*";
                  }
       
                  @Override
                  public ClientHttpResponse fallbackResponse() {
                      return new ClientHttpResponse() {
                          @Override
                          public HttpStatus getStatusCode() throws IOException {
                              return HttpStatus.OK;
                          }
       
                          @Override
                          public int getRawStatusCode() throws IOException {
                              return 200;
                          }
       
                          @Override
                          public String getStatusText() throws IOException {
                              return "OK";
                          }
       
                          @Override
                          public void close() {
       
                          }
       
                          @Override
                          public InputStream getBody() throws IOException {
                              return new ByteArrayInputStream("error, I'm the fallback".getBytes());
                          }
       
                          @Override
                          public HttpHeaders getHeaders() {
                              HttpHeaders headers = new HttpHeaders();
                              headers.setContentType(MediaType.APPLICATION_JSON);
                              return headers;
                          }
                      };
                  }
              }